Novel ability of diflubenzuron as an inhibitor of mitochondrial function

Compounds classified as benzoylphenylurea (BPU), such as diflubenzuron (DFB), are used as insecticides. Although BPU disrupts molting by inhibiting chitin biosynthesis and exhibits insecticidal activity, their exact mode of action remains unknown. Since epidermal cells proliferate and morphologically change from squamous to columnar cells during the early stages of insect molting, we speculate that a transition similar to that from epithelium to mesenchyme occurs and that BPU may inhibit this transition. Here, we addressed this possibility. We found that DFB decreases actin expression in insect cells (the tissue cultures of insect integument). Detailed analysis in Schneider S2 cells reveals that DFB inhibits the expression of actin isoforms (Act5C and Act42A) and the Drosophila ortholog of myocardin-related transcription factor (Mrtf), leading to cell growth suppression. Proteomics identified the Drosophila ortholog of prohibitin (Phb1D and Phb2E) as one of the DFB-binding proteins. DFB inhibits the interaction between Phb1D and Phb2E and induces mitochondrial dysfunction. The knock-down of Phb2E suppresses the expression of Act5C, Act42A, and Mrtf, leading to cell growth inhibition. Thus, the disruption of Phb function is a possible novel target of DFB.

Chemical synthesis and functional characterization of LaIT3, an insecticidal two-domain peptide in Liocheles australasiae venom

LaIT3, belonging to the β-KTx family, is an insecticidal peptide in the venom of the Liocheles australasiae scorpion. Peptides in the family consist of two structural domains: an N-terminal domain with an α-helical structure common to antimicrobial peptides and a C-terminal domain with a structure stabilized by three disulfide bonds common to ion-channel blocking peptides. However, the contribution of each domain of LaIT3 to its activity remained unknown. In addition, some peptidic components are known to be enzymatically cleaved in the venom, which generates partial peptides. In our study, we searched for partial peptides of LaIT3 using LC/MS analysis and found peptides generated by cleavage at the central region of LaIT3. We subsequently synthesized full-length LaIT3 and its partial peptides to evaluate their insecticidal activity. The results, showing that only full-length LaIT3 is active, indicate that the insecticidal activity of LaIT3 depends on the presence of both N-terminal and C-terminal domains. Furthermore, LaIT3 did not exhibit the cytolytic activity against insect cells and showed only weak antibacterial activity. These findings suggest that its action is not due to a simple membrane disruption effect but instead due to actions on specific target molecules, including ion channels.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Health-Related Quality of Life at Five Years for a Randomized Trial of Tri-Modality Therapy with I-125 Brachytherapy, External Beam Radiation Therapy, and Short- vs. Long-Term Androgen Deprivation Therapy for High-Risk Localized Prostate Cancer (TRIP)

PURPOSE/OBJECTIVE(S)

To describe the patient-reported health-related quality of life (HR-QoL) outcomes at five years for a multicenter randomized trial of tri-modality therapy with iodine-125 brachytherapy, external beam radiation therapy (EBRT), and short- versus long-term androgen deprivation therapy (ADT) for high-risk localized prostate cancer (TRIP/TRIGU0907).

MATERIALS/METHODS

A total of 332 men with high-risk prostate cancer were randomized to either 6 months of ADT (n = 165) or 30 months of ADT (n = 167) in conjunction with combined modality radiation therapy. For the HR-QoL assessment, general HR-QoL and disease-specific HR-QoL were measured using the Japanese version of the Medical Outcomes Study 8-items Short-Form Health Survey (SF-8) and the Expanded Prostate Cancer Index Composite (EPIC). Patient-reported outcome questionnaires were filled out before ADT initiation, and five years after. Scores were reported as mean with the standard deviation. QoL end points were assessed as the change between pre and post treatment using paired student t-test. Changes in the International Prostate Symptom Scores (IPSS) score, including total score and subscores, were also evaluated. The study was powered according to the primary endpoint of biochemical progression free survival with HR-QoL as a secondary endpoint. In addition, recovery of testosterone level (300ng/dL or higher) was calculated as the cumulative incidence curve and compared between arms by log-rank test.

RESULTS

The cumulative incidence of biochemical progression, and salvage ADT treatment were not different between the arms. Mean domain scores at baseline were well balanced between the two arms in all HR-QoL. There were no differences in the SF-8 assessment and the total and subscore EPIC assessments between the arms. The average sexual function score was lower in short arm versus long arm; 16.24 versus 20.24 at baseline, but not different at five years, 9.96 versus 7.78 (p = 0.164). There were no significant differences between the arms for the total and subscore IPSS. Significantly higher percentage of patients, 71.7% in the short arm recovered to a normal testosterone level at 6 years after the initiation of ADT compared to 43.2% in long arm (p<0.0001).

CONCLUSION

At five years after ADT initiation, there were no significant differences in all score changes between the two arms with general HR-QoL and disease-specific HR-QoL. Most of HR-QoL returned to baseline level, and sexual function scores were low from baseline in this population. Two-years' adjuvant ADT did not affect HR-QoL at five years, although it significantly retarded testosterone recovery compared to 6 months of hormone therapy.

A social system to disperse the irrigation start date based on the spatial public goods game

In paddy rice cultivation, the amount of water used during the beginning of the irrigation season is the highest. However, there is a possibility of a water shortage at this season as climate change decreases snowfall. In this study, we propose new schemes based on the public goods game to reduce peak water volume during this season by dispersing the irrigation start dates. In our agent-based model, agents determine the irrigation start date based on the evolutionary game theory. This model considers the economic variables of individual farmers (e.g., gross cultivation profit and cultivation cost), the cost and subsidy for cooperation for the dispersion of the irrigation start dates, and the information-sharing network between farmers. Individual farmers update the cooperation/defection strategy at each time step based on their payoffs. Using this agent-based model simulation, we investigate a scheme that maximizes the dispersion of irrigation start dates among multiple scheme candidates. The results of the simulation show that, under the schemes in which one farmer belongs to a group and the groups do not overlap, the number of cooperating farmers did not increase, and the dispersion of irrigation start dates barely increased. By adopting a scheme in which one farmer belongs to multiple groups and the groups overlap, the number of cooperating farmers increased, while the dispersion of irrigation start dates maximized. Furthermore, the proposed schemes require the government to obtain information about the number of cooperators in each group to determine the subsidy amount. Therefore, we also proposed the method which allows estimating the number of cooperators in each group through the dispersion of irrigation start dates. This significantly reduces the cost of running the schemes and provides subsidization and policy evaluations unaffected by false declarations of farmers.

Ultrafast time-resolved 2D imaging of laser-driven fast electron transport in solid density matter using an x-ray free electron laser

High-power, short-pulse laser-driven fast electrons can rapidly heat and ionize a high-density target before it hydrodynamically expands. The transport of such electrons within a solid target has been studied using two-dimensional (2D) imaging of electron-induced Kα radiation. However, it is currently limited to no or picosecond scale temporal resolutions. Here, we demonstrate femtosecond time-resolved 2D imaging of fast electron transport in a solid copper foil using the SACLA x-ray free electron laser (XFEL). An unfocused collimated x-ray beam produced transmission images with sub-micron and ∼10 fs resolutions. The XFEL beam, tuned to its photon energy slightly above the Cu K-edge, enabled 2D imaging of transmission changes induced by electron isochoric heating. Time-resolved measurements obtained by varying the time delay between the x-ray probe and the optical laser show that the signature of the electron-heated region expands at ∼25% of the speed of light in a picosecond duration. Time-integrated Cu Kα images support the electron energy and propagation distance observed with the transmission imaging. The x-ray near-edge transmission imaging with a tunable XFEL beam could be broadly applicable for imaging isochorically heated targets by laser-driven relativistic electrons, energetic protons, or an intense x-ray beam.

Role of CRP2-MRTF interaction in functions of myofibroblasts

Inflammatory response induces phenotypic modulation of fibroblasts into myofibroblasts. Although transforming growth factor-βs (TGF-βs) evoke such transition, the details of the mechanism are still unknown. Here, we report that a LIM domain protein, cysteine-and glycine-rich protein 2 (CSRP2 [CRP2]) plays a vital role in the functional expression profile in myofibroblasts and cancer-associated fibroblasts (CAFs). Knock-down of CRP2 severely inhibits the expression of smooth muscle cell (SMC) genes, cell motility, and CAF-mediated collective invasion of epidermoid carcinoma. We elucidate the following molecular bases: CRP2 directly binds to myocardin-related transcription factors (MRTF-A/B [MRTFs]) and serum response factor (SRF) and stabilizes the MRTF/SRF/CArG-box complex to activate SMC gene expression. Furthermore, a three-dimensional structural analysis of CRP2 identifies the amino acids required for the CRP2-MRTF-A interaction. Polar amino acids in the C-terminal half (serine-152, glutamate-154, serine-155, threonine-156, threonine-157, and threonine-159 in human CRP2) are responsible for direct binding to MRTF-A. On the other hand, hydrophobic amino acids outside the consensus sequence of the LIM domain (tryptophan-139, phenylalanine-144, leucine-153, and leucine-158 in human CRP2) play a role in stabilizing the unique structure of the LIM domain.Key words: CRP2, 3D structure, myocardin-related transcription factor, myofibroblast, cancer-associated fibroblasts.

Molecular Diversity of Linear Peptides Revealed by Transcriptomic Analysis of the Venom Gland of the Spider Lycosa poonaensis

Spider venom is a complex mixture of bioactive components. Previously, we identified two linear peptides in Lycosa poonaensis venom using mass spectrometric analysis and predicted the presence of more linear peptides therein. In this study, a transcriptomic analysis of the L. poonaensis venom gland was conducted to identify other undetermined linear peptides in the venom. The results identified 87 contigs encoding peptides and proteins in the venom that were similar to those in other spider venoms. The number of contigs identified as neurotoxins was the highest, and 15 contigs encoding 17 linear peptide sequences were identified. Seven peptides that were representative of each family were chemically synthesized, and their biological activities were evaluated. All peptides showed significant antibacterial activity against Gram-positive and Gram-negative bacteria, although their selectivity for bacterial species differed. All peptides also exhibited paralytic activity against crickets, but none showed hemolytic activity. The secondary structure analysis based on the circular dichroism spectroscopy showed that all these peptides adopt an amphiphilic α-helical structure. Their activities appear to depend on the net charge, the arrangement of basic and acidic residues, and the hydrophobicity of the peptides.

Calmodulinopathy is a common cause of critical cardiac phenotypes in fetus and infancy

Background

Cardiac calmodulinopathy is a life-threatening arrhythmia syndrome which presents several phenotypes of inherited primary arrhythmia syndrome (IPAS), and caused by mutations in calmodulin-encoded genes (CALM1–3). We aimed clarify the frequency and their clinical characteristics of calmodulinopathy in our IPAS cohort.

Methods

By using next generation sequencing, we screened arrhythmia related genes including calmodulin-encoding genes in 322 unrelated symptomatic children (0–12 years) who were suspected as IPAS; they included 40 cases with lethal arrhythmic attacks (LAE) under 6-year-old. After gene screening, we investigated their physiological and clinical characteristics about mutation carriers.

Results

Among 322 children, we identified 6 mutations of calmodulin-encoded genes in 9 probands (2.8%); one CALM1 in 2 probands (N98S), and 5 CALM2 in 7 probands (E46K, D96V, D96G, N98S, E141K). Their clinical diagnoses were long QT syndrome (LQTS, n=4), catecholaminergic polymorphic ventricular tachycardia (CPVT, n=3) and both (n=2). Their age of diagnosis ranges at 0–9 with the median of 5 years. There were three major clinical phenotypes; 1) CALM2-D96V, and E141K: two infants with advanced atrio-ventricular block, significant QTc prolongation, severe heart failure from their fetal period – both of them deceased within 1.5-year-old. Their clinical phenotypes resembled classical Timothy syndrome caused by CACNA1C mutations. 2) CALM1-N98S (n=2), CALM2-N98S (n=2), and CALM2-D96G: four preschoolers with LAEs and one syncope: all of them were 3–5 years old. In addition, a T wave morphology of CALM2-D96G carrier was very similar to LQT1. 3) CALM2-E46K (n=2): two were first diagnosed with neurological and developmental disorders, and showed phenotype of CPVT: their cardiac phenotypes were milder compared with that of 1) or 2). Overall, these phenotypes seemed to be mutation specific (indicated in figure). Their cardiac features were severer, and the onset of LAEs was earlier compared with other genotypes of LQTS/CPVT. As the treatment, β-blocker was effective for control of LAEs.

Conclusion

Cardiac calmodulinopathy presented serious and potentially lethal phenotypes in fetus or infancy. To prevent cardiac death in them, we must correctly diagnose and start the treatment as earlier as possible.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): MEXT KAKENHI from the Ministry of Education, Culture, Sports, Science, and Technology of Japan

Insight into the relationship between heart rate and mortality in patients in sinus rhythm with heart failure with preserved ejection fraction

Background

There are several reports showing that elevated heart rate (HR) is associated with poor outcomes in patients in sinus rhythm (SR) with heart failure with preserved ejection fraction (HFpEF), although the association is weak or none in HFpEF patients with atrial fibrillation (Af). However, in previous studies, cardiac and non-cardiac factors which may be associated with elevated HR, have not been fully adjusted for.

Purpose

The purpose of this study is to explore covariates of elevated HR and to investigate the relationship between heart rate and mortality in HFpEF patients in SR.

Methods and results

Of the 1161 patients, who registered prospective multicenter, observational study of patients with HFpEF (PURSUIT-HFpEF), 726 patients in SR were examined. We performed laboratory testing and echocardiography in the compensated stage (in stable condition after treatment of acute decompensated HF). Geriatric nutritional risk index (GNRI) was calculated as nutrition index. Resting heart rate (HR) was analyzed as categorical (tertiles, T1–3). We followed the patients for median of 598 days (interquartile range 329–1028 days) to observe the outcome all-cause mortality.

The Kaplan analysis revealed that there was a significant difference between heart rate and mortality (log-rank, p=0.001). Characteristics were compared between patients in T1 (HR ≤63) and T3 (HR ≥75). There were no differences in cardiac factors between patients in T1 and T3. C-reactive protein (CRP) was significantly higher in patients in T3 than those in T1 (p=0.0004,). GNRI was significantly lower in patients in T3 than those in T1 (p=0.001). After adjustment for covariates including N-terminal pro-B type natriuretic peptide and estimated glomerular filtration rate, CRP and GNRI significantly correlated with HR (continuous variable) by multiple regression analysis (beta-coefficient = 1.52, p=0.003 and beta-coefficient = −0.14, p=0.04, respectively). Taking T1 as the reference, multivariable Cox regression analysis revealed that T3 was independently associated with mortality (hazard ratio: 2.10, 95% confidence interval: 1.33–3.32, p=0.001).

Conclusion

Although elevated HR was associated with enhanced inflammation and malnutrition, it itself was an independent predictor of death in HFpEF patients in SR.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Roche Diagnosis K.K.Fuji Film Toyama Chemical Co. Ltd.

A luciferase reporter assay for ecdysone agonists using HEK293T cells

Ecdysone agonists are a class of insecticides that activate the ecdysone receptor (EcR) heterodimerized with the ultraspiracle (USP). Here, we report a new luciferase reporter assay for ecdysone agonists. The assay employs mammalian HEK293T cells transiently transfected with the EcR and USP genes of Chilo suppressalis, along with the taiman (Tai) gene of Drosophila melanogaster that encodes a steroid receptor coactivator. This assay system gave results consistent with those of radioligand binding assays and showed sensitivity superior to that of the existing in vitro methods. In addition, use of the heterologous host cells precludes perturbation from intrinsic players of the ecdysone signaling, which is a potential drawback of insect cell-based methods. This reporter system is suitable for detailed structure-activity analysis of ecdysone agonists and will serve as a valuable tool for the rational design of novel insect growth regulators.

High-power laser experiment on developing supercritical shock propagating in homogeneously magnetized plasma of ambient gas origin

A developing supercritical collisionless shock propagating in a homogeneously magnetized plasma of ambient gas origin having higher uniformity than the previous experiments is formed by using high-power laser experiment. The ambient plasma is not contaminated by the plasma produced in the early time after the laser shot. While the observed developing shock does not have stationary downstream structure, it possesses some characteristics of a magnetized supercritical shock, which are supported by a one-dimensional full particle-in-cell simulation taking the effect of finite time of laser-target interaction into account.

Structure modification of nonsteroidal brassinolide-like compound, NSBR1

Brassinolide (BL) is a possible plant growth regulator in agriculture, but the presence of a steroid skeleton hampers the field application of BL in agriculture because of its high synthetic cost. We discovered NSBR1 as the first nonsteroidal BL-like compound using in silico technology. Searching for more potent BL-like compounds, we modified the structure of NSBR1 with respect to two benzene rings and the piperazine ring. The activity of synthesized compounds was measured in Arabidopsis hypocotyl elongation. The propyl group of butyryl moiety of NSBR1 was changed to various alkyl groups, such as straight, branched, and cyclic alkyl chains. Another substituent, F, at the ortho-position of the B-ring toward the piperazine ring was changed to other substituents. A methyl group was introduced to the piperazine ring. Most of the newly synthesized compounds with the 3,4-(OH)2 group at the A-ring significantly elongated the hypocotyl of Arabidopsis.

Permeability of the fish intestinal membrane to bulky chemicals

The ability to predict the environmental behavior of chemicals precisely is important for realizing more rational regulation. In this study, the bioaccumulation of nine chemicals of different molecular weights absorbed via the intestinal tract was evaluated in fish using the everted gut sac method. The amounts of chemicals that passed through the intestinal membrane after a 24-hr exposure were significantly decreased for chemicals with MW≥548 and D_{max min}≥15.8 Å (or D_{max aver}≥17.2 Å). These thresholds are consistent with those previously proposed in terms of MW (>800) and molecular size (D_{max min}>15.6 Å or D_{max aver}>17.1 Å) for the limit of permeable chemicals through the gill membrane. The results show that the same MW and D_max criteria can be used to predict low bioaccumulation through both the gill membrane and the intestinal tract. These findings are helpful in reducing the need to conduct animal tests in environmental safety studies.

Criterion of molecular size to evaluate the bioaccumulation potential of chemicals in fish

To evaluate the bioaccumulation potential of chemicals in fish, a molecular-size descriptor, D_{max aver}, has been used as a weight of evidence under the EU REACH. The D_{max aver} value, however, is estimated on the basis of 3-D structures of possible stable conformers in a vacuum using OASIS software that requires expertise upon parameter input. We developed a method to calculate the 3-D conformers in water, which is more suitable for bioaccumulation potential evaluation in an aquatic environment, by introducing MD simulation. By examining the relationship of the calculated molecular size of 1665 chemicals with their reported BCF values, we found that 17.1 Å of D_{max aver} or 15.6 Å of D_{max min} was a threshold of molecular size in water to predict the low bioaccumulation (i.e., BCF<5000) of a chemical. Setting this threshold as a new standard would reduce the number of animal tests without compromising the quality of safety evaluation.

High-power laser experiment forming a supercritical collisionless shock in a magnetized uniform plasma at rest

We present an experimental method to generate quasiperpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counterstreaming magnetized N flows. Namely, we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.

Characteristics and prognosis in heart failure with preserved ejection fraction patients without left ventricular hypertrophy

Background

Clinical heterogeneity exists in heart failure with preserved ejection fraction (HFpEF). Left ventricular (LV) structure in HFPEF is characterized by normal LV cavity size and LV hypertrophy (LVH). However some of HFPEF patients do not have LV hypertrophy, and these patients may have distinct characteristics,

Purpose

The purpose of this study is to clarify the clinical characteristics and the prognosis for HFPEF patients without LVH.

Methods

We studied 1097 patients, who were hospitalized for acute decompensated heart failure with LVEF ≥50%, and enrolled in the PURSUIT-HFpEF registry. Laboratory testing and echocardiography were examined in the compensated stage (in stable condition after treatment of acute decompensated HF). We divided these patients into 2 groups based on LV mass index (LVMI) in the compensated stage according to the American Society of Echocardiography/European Association of Cardiovascular Imaging recommendations; patients with LVH (48%) and those without LVH (52%).

Results

Patients without LVH had significantly lower levels of C-reactive protein and N-terminal pro brain natriuretic peptide (NT-proBNP) and higher levels of estimated glomerular filtration rate in the compensated stage than those with it (p&lt;0.05 for all). Cox hazard regression analysis showed that absence of LVH was favorably associated with the primary composite endpoint of all-cause death, HF rehospitalization, and cerebrovascular events (hazard ratio 0.776, 95% confidence interval 0.620-to 0.970, p&lt;0.05).

On the other hand, the frequency of atrial fibrillation (Af) in the decompensated stage was higher in patients without LVH than those with it (52.1% vs 39.3%, p&lt;0.001). Multivariate logistic analysis showed that absence of LVH was independently associated with presence of Af in the decompensated stage (odds ratio=1.520, 95% confidence interval 1.130 to 2.050, P&lt;0.01)

Conclusions

HFPEF patients without LVH have less organ damage and favorable prognosis. Af may play a role in the decompensation of HF in HFPEF patients without LVH.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Roche Diagnostics K.K. (Grant number: not applicable)Fuji Film Toyama Chemical Co., Ltd. (Grant number: not applicable)

Effects of brassinolide on the growing of rice plants

Brassinosteroids are plant steroid hormones that are essential for plant growth. When germinated rice seeds were treated with brassinolide (BL), stems were elongated and root spiral formation was observed at 5 nM of BL. Such root spiral formation was not induced by other plant hormones such as auxin and gibberellin. Since weak non-steroidal brassinolide-like compound (NSBR1) also induced spiral formation, this root spiral induction can be used as the index in the search for BL-like compounds.

Detection of juvenile hormone agonists by a new reporter gene assay using yeast expressing Drosophila methoprene-tolerant

Juvenile hormones (JHs) are sesquiterpenoids that play important roles in the regulation of growth, metamorphosis, and reproduction in insects. Synthetic JH agonists (JHAs) have been used as insecticides and are categorized as a class of insect growth regulators (IGRs). Natural JHs and synthetic JHAs bind to the JH receptor methoprene‐tolerant (Met), which forms a functional JH‐receptor complex with steroid receptor coactivators, such as Drosophila melanogaster Taiman (Tai). The ligand‐bound Met–Tai complex induces the transcription of JH response genes by binding to specific DNA elements referred to as JH response elements (JHREs). In the present study, we established a reporter gene assay (RGA) for detecting natural JHs and synthetic JHAs in a yeast strain expressing D. melanogaster Met and Tai. The yeast RGA system detected various juvenoid ligands in a dose‐dependent manner. The rank order of the ligand potencies of the juvenoids examined in the yeast RGA linearly correlated with those of RGAs for Met–Tai established in mammalian and insect cells. Our new yeast RGA is rapid, easy to handle, cost‐effective, and valuable for screening novel JHAs.

A Commercial Extract of Cyanotis arachnoidea Roots as a Source of Unusual Ecdysteroid Derivatives with Insect Hormone Receptor Binding Activity

Ecdysteroids act as molting hormones in insects and as nonhormonal anabolic agents and adaptogens in mammals. A wide range of ecdysteroid-containing herbal extracts are available worldwide as food supplements. The aim of this work was to study such an extract as a possible industrial source of new bioactive ecdysteroids. A large-scale chromatographic isolation was performed from an extract of Cyanotis arachnoidea roots. Ten ecdysteroids (1-10) including eight new compounds were isolated and characterized by extensive nuclear magnetic resonance studies. Highly unusual structures were identified, including a H-14β (1, 2, 4, and 10) moiety, among which a 14β(H)17β(H) phytosteroid (1) is reported for the first time. Compounds with an intact side chain (4-10) and 11 other natural or semisynthetic ecdysteroids (11-21) were tested for insect ecdysteroid receptor (EcR) binding activity. Two new compounds, i.e., 14-deoxydacryhainansterone (5) and 22-oxodacryhainansterone (6), showed strong EcR binding activity (IC50 = 41.7 and 380 nM, respectively). Six compounds were identified as EcR agonists and another two as antagonists using a transgenic ecdysteroid reporter gene assay. The present results demonstrate that commercial C. arachnoidea extracts are rich in new, unusual bioactive ecdysteroids. Because of the lack of an authentic plant material, the truly biosynthetic or artifactual nature of these compounds cannot be confirmed.

Characterization of 2 linear peptides without disulfide bridges from the venom of the spider Lycosa poonaensis (Lycosidae)

Spider venom is a complex mixture of bioactive components, in which peptides play an important role by showing neurotoxicity or cytotoxicity. Disulfide-rich peptides are major components in the venom, but linear peptides without disulfide bridges are also present and often show antimicrobial activity. In this study, we analyzed the venom of the spider Lycosa poonaensis (Lycosidae) to find novel antimicrobial peptides using mass spectrometry. The result revealed that 120 out of 401 detected components were nondisulfide-bridged peptides. From them, the sequence of 2 peptides (lyp2370 and lyp1987) were determined by MS/MS analysis. The biological activity test revealed that lyp2370 has only weak antibacterial activity. On the other hand, lyp1987, which is identical to M-lycotoxin-Ls3b from the Lycosa singoriensi venom, showed significant antibacterial activity. The weak activity of lyp2370 was found to be due to the presence of a Glu residue on the hydrophilic face of its amphipathic α-helical structure.

Inhibition of fibrotic changes in infrapatellar fat pad alleviates persistent pain and articular cartilage degeneration in monoiodoacetic acid-induced rat arthritis model

OBJECTIVE

We have reported that fibrotic changes in infrapatellar fat pad (IFP) after acute joint inflammation are closely associated with persistent pain in rats. In this study, to examine the effects of anti-fibrotic treatment on persistent pain, we used C-type natriuretic peptides (CNP) at the recovery phase after acute joint inflammation.

DESIGN

Thirty-two male Wistar rats were used in this study. Monoiodoacetic acid (MIA) was injected intra-articularly to induce IFP fibrosis and persistent pain. CNP was injected after acute inflammatory phase in the same knee joint. Time-course pain-avoidance behavior tests and histological analyses were performed to examine the effects of CNP.

RESULTS

Histological evaluations indicated that intra-articular injection of CNP inhibited fibrotic changes in IFP after acute inflammation. Incapacitance tests indicated that MIA injection into rat knee joint quickly decreased the percent weight on ipsilateral limb. In the vehicle group, the decrease was maintained up to day 28, suggesting that pain persistence occurred after acute inflammation (Day 0/Day 28, Est Dif -8.15, CI -10.78∼-5.53, Linear mixed-effect model). In contrast, the pain was alleviated in the CNP group after day 14 (Day0/Day 14, -0.51, -2.62-1.59). In addition, we observed significant improvement in the degree of articular cartilage degeneration at day 14 in the CNP group (OARSI score: vehicle 16.14 ± 4.37 vs CNP 6.87 ± 3.44, P < 0.01; Wilcoxon rank sum test).

CONCLUSION

Fibrotic changes in IFP may play important roles in both persistent pain and articular cartilage degeneration.

Nonsteroidal ecdysone receptor agonists use a water channel for binding to the ecdysone receptor complex EcR/USP

The ecdysone receptor (EcR) possesses the remarkable capacity to adapt structurally to different types of ligands. EcR binds ecdysteroids, including 20-hydroxyecdysone (20E), as well as nonsteroidal synthetic agonists such as insecticidal dibenzoylhydrazines (DBHs). Here, we report the crystal structures of the ligand-binding domains of Heliothis virescens EcR/USP bound to the DBH agonist BYI09181 and to the imidazole-type compound BYI08346. The region delineated by helices H7 and H10 opens up to tightly fit a phenyl ring of the ligands to an extent that depends on the bulkiness of ring substituent. In the structure of 20E-bound EcR, this part of the ligand-binding pocket (LBP) contains a channel filled by water molecules that form an intricate hydrogen bond network between 20E and LBP. The water channel present in the nuclear receptor bound to its natural hormone acts as a critical molecular adaptation spring used to accommodate synthetic agonists inside its binding cavity.

Receptor-binding affinity and larvicidal activity of tetrahydroquinoline-type ecdysone agonists against Aedes albopictus

Tetrahydroquinolines (THQs), a class of nonsteroidal ecdysone agonists, are good candidates for novel mosquito control agents because they specifically bind to mosquito ecdysone receptors (EcRs). We have recently performed quantitative structure-activity relationship (QSAR) analyses of THQs to elucidate the physicochemical properties important for the ligand-receptor interaction. Based on previous QSAR results, here, we newly synthesized 15 THQ analogs with a heteroaryl group at the acyl moiety and evaluated their binding affinity against Aedes albopictus EcRs. We also measured the larvicidal activity of the combined set of previously and newly synthesized compounds against A. albopictus to examine the contribution of receptor-binding to larvicidal activity. Multiple regression analyses showed that the binding affinity and the molecular hydrophobicity of THQs are the key determinants of their larvicidal activity.

Isoxaben analogs inhibit chitin synthesis in the cultured integument of the rice stem borer Chilo suppressalis

Benzoylphenylureas (BPUs) were discovered as novel type insecticides about a half century ago; many analogs have been launched as insecticides and acaricides. BPUs are known to inhibit chitin synthesis in insects and other arthropods, but they have no effect against microorganisms such as fungi. We designed new chitin synthesis inhibitors based on the hypothesis that biomolecules that play important roles in cellulose and chitin biosynthesis are similar. In the full automatic modeling system (FAMS), the cellulose synthase was selected as a template three-dimensional structure. Thus, we focused on the structure of cellulose synthase inhibitor, isoxaben, to develop new chemistry. The 1,1-diethylethyl [-C(CH₃)(CH₂CH₃)₂] group of isoxaben was changed to a 4-substituted phenyl group bearing Cl, Et, or Ph. These compounds significantly inhibited chitin synthesis in the cultured integument of the rice stem borer Chilo suppressalis. The activity of the 4-ethylphenyl analog was enhanced 30-fold by adding piperonyl butoxide to the culture medium.

Virtual screening identifies a novel piperazine-based insect juvenile hormone agonist

Juvenile hormone (JH) agonists constitute a subclass of insect growth regulators and play important roles in insect pest management. In this work, a multi-step virtual screening program was executed to find novel JH agonists. A database of 5 million purchasable compounds was sequentially processed with three computational filters: (i) shape and chemical similarity as compared to known JH-active compounds; (ii) molecular docking simulations against a Drosophila JH receptor, methoprene-tolerant; and (iii) free energy calculation of ligand-receptor binding using a modified MM/PBSA (molecular mechanics/Poisson-Boltzmann surface area) protocol. The 11 candidates that passed the three filters were evaluated in a luciferase reporter assay, leading to the identification of a hit compound that contains a piperazine ring system (EC₅₀=870 nM). This compound is structurally dissimilar to known JH agonists and synthetically easy to access; therefore, it is a promising starting point for further structure optimization.

Identification of an antiviral component from the venom of the scorpion Liocheles australasiae using transcriptomic and mass spectrometric analyses

Scorpion venom contains a variety of biologically active peptides. Among them, neurotoxins are major components in the venom, but it also contains peptides that show antimicrobial activity. Previously, we identified three insecticidal peptides from the venom of the Liocheles australasiae scorpion, but activities and structures of other venom components remained unknown. In this study, we performed a transcriptome analysis of the venom gland of the scorpion L. australasiae to gain a comprehensive understanding of its venom components. The result shows that potassium channel toxin-like peptides were the most diverse, whereas only a limited number of sodium channel toxin-like peptides were observed. In addition to these neurotoxin-like peptides, many non-disulfide-bridged peptides were identified, suggesting that these components have some critical roles in the L. australasiae venom. In this study, we also isolated a component with antiviral activity against hepatitis C virus using a bioassay-guided fractionation approach. By integrating mass spectrometric and transcriptomic data, we successfully identified LaPLA₂-1 as an anti-HCV component. LaPLA₂-1 is a phospholipase A₂ having a heterodimeric structure that is N-glycosylated at the N-terminal region. Since the antiviral activity of LaPLA₂-1 was inhibited by a PLA₂ inhibitor, the enzymatic activity of LaPLA₂-1 is likely to be involved in its antiviral activity.

High-density lipoprotein cholesterol does not predict future cardiovascular events in patients treated with statins for secondary prevention: an observation from the REAL-CAD study

Background

The relation between high-density lipoprotein cholesterol (HDL-C) level after statin therapy and cardiovascular events in patients with stable coronary artery disease remains unclear.

Purpose

We sought to determine the association of the HDL-C level after statin therapy with cardiovascular events in stable coronary artery disease patients.

Methods

This study was a post-hoc analysis of the Randomized Evaluation of Aggressive or Moderate Lipid Lowering Therapy with Pitavastatin in Coronary Artery Disease (REAL-CAD) study, which is randomised, open-label, blinded endpoint, physician-initiated, superiority clinical trial. Enrollment was from January 2010 to March 2013, and follow-up was through January 2016. From the main study, we excluded the patients without either HDL-C data at baseline or 6 months, with occurrence of the primary outcome at 6 months and reported poor adherence for pitavastatin. The primary outcome of interest was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, or unstable angina requiring emergent admission after 6 months from randomisation, consistent with the primary analysis of the trial. We constructed landmark Cox proportional hazards regression models with the 18 selected clinically relevant risk-adjusting variables during the entire follow-up period starting at 6 months after randomisation. Absolute and relative changes of HDL-C level were defined as (6 months value – baseline value) and (absolute change / baseline value) × 100, respectively.

Results

Among 14,774 participants in the REAL-CAD study, 9,221 patients were included in this analysis (7652 [83.0%] male; median [IQR] age, 70 [63–75] years; median [IQR] HDL-C, 49 [42–57] mg/dL; median [IQR] low-density lipoprotein cholesterol [LDL-C], 88 [75–101] mg/dL). During a median follow-up period of 4.0 (IQR 3.2–4.7) years, the primary outcome occurred in 417 (4.5%) patients. There was no significant difference in crude and adjusted cumulative incidence of the primary outcome among the quartiles of HDL-C level at 6 months (Figure 1). The adjusted risks of all the HDL-C related variables (baseline value, 6 months value, absolute and relative changes) for the primary outcome were not significant (Figure 2). Furthermore, the adjusted hazard ratio (HR) as HDL-C level at 6 months increased by 10 mg/dL remained non-significant for the primary outcome for each on-treatment LDL-C level at 6 months (&lt;70 mg/dL [HR 0.97, 95% CI 0.82–1.15], 70–100 mg/dL [HR 1.10, 95% CI 0.98–1.24], and ≥100 mg/dL [HR 0.94, 95% CI 0.78–1.13]). There was also no significant association between HDL-C level at 6 months and the primary outcome both in the low (1 mg/day [HR 1.02, 95% CI 0.91–1.14], increased by 10 mg/dL) dose and high (4 mg/day [HR 1.04, 95% CI 0.91–1.19]) dose pitavastatin groups

Conclusion

After statin therapy with modestly controlled LDL-C, HDL-C level has little prognostic value in patients with stable coronary artery disease.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): The Comprehensive Support Project for Clinical Research of Lifestyle-Related Disease of the Public Health Research Foundation

NRSF-GNAO1-CaMK2 axis exacerbates cardiac remodeling and progresses heart failure by impairing Ca2+ homeostasis

Background

In the development of heart failure, pathological intracellular signaling reactivates fetal cardiac genes, which leads to maladaptive remodeling and cardiac dysfunction. We previously reported that a transcriptional repressor, neuron restrictive silencer factor (NRSF) represses fetal cardiac genes and maintains normal cardiac function under normal conditions, while hypertrophic stimuli de-repress this NRSF mediated repression via activation of CaMKII. Molecular mechanisms by which NRSF maintains cardiac systolic function remains to be determined, however.

Purpose

To elucidate how NRSF maintains normal cardiac homeostasis and identify the novel therapeutic targets for heart failure.

Methods and results

We generated cardiac-specific NRSF knockout mice (NRSF cKO), and found that these NRSF cKO showed cardiac dysfunction and premature deaths accompanied with lethal arrhythmias, as was observed in our previously reported cardiac-specific dominant-negative mutant of NRSF transgenic mice (dnNRSF-Tg).

By cDNA microarray analysis of dnNRSF-Tg and NRSF-cKO, we identified that expression of Gnao1 gene encoding Gαo, a member of inhibitory G proteins, was commonly increased in ventricles of both types of mice.

ChIP-seq analysis, reporter assay and electrophoretic mobility shift assay identified that NRSF transcriptionally regulates Gnao1 gene expression.

Genetic Knockdown of Gαo in dnNRSF-Tg and NRSF-cKO by crossing these mice with Gnao1 knockout mice ameliorated the reduced systolic function, increased arrhythmogenicity and reduced survival rates.

Transgenic mice expressing a human GNAO1 in their hearts (GNAO1-Tg) showed progressive cardiac dysfunction with cardiac dilation. Ventricles obtained from GNAO1-Tg have increased phosphorylation level of CaMKII and increased expression level of endogenous mouse Gnao1 gene. These data suggest that increased cardiac expression of Gαo is sufficient to induce pathological Ca2+-dependent signaling and cardiac dysfunction, and that Gαo forms a positive regulatory circuit with CaMKII and NRSF.

Electrophysiological analysis in ventricular myocytes of dnNRSF-Tg revealed that impaired Ca2+ handling via alterations in localized L-type calcium channel (LTCC) activities; decreased T-tubular and increased surface sarcolemmal LTCC activities, underlies Gαo-mediated cardiac dysfunction.

Furthermore, we also identified increased expression of Gαo in ventricles of two different heart failure mice models, mice with transverse aortic constriction and mice carrying a mutant cardiac troponin T, and confirmed that genetic reduction of Gαo prevented the progression of cardiac dysfunction in both types of mice.

Conclusions

Increased expression of Gαo, induced by attenuation of NRSF-mediated repression forms a pathological circuit via activation of CaMKII. This circuit exacerbates cardiac remodeling and progresses heart failure by impairing Ca2+ homeostasis. Gαo is a potential therapeutic target for heart failure.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grants-in –Aid for Scientific Research from the Japan Society for the Promotion of Science

Transcription-inducing activity of natural and synthetic juvenile hormone agonists through the Drosophila Methoprene-tolerant protein

BACKGROUND

Juvenile hormones (JHs) are a class of sesquiterpenoids that play a pivotal role in insect growth and reproduction. Synthetic JH agonists (JHAs), including pyriproxyfen, have been widely used as insecticides to control agricultural pests and disease vectors. The antimetamorphic action of JHAs is mediated by their intracellular receptor, the heterodimer of Methoprene-tolerant (Met) and Taiman (Tai) proteins. Although a range of bioassay systems has been developed to detect the activity of JHAs, each of these systems has its own drawback(s), such as poor reproducibility, the use of radioactive ligands or the effect of endogenous JH-signaling factors.

RESULTS

To address these issues, we constructed a new luciferase reporter assay for JHAs in mammalian HEK293T cells transiently transfected with the Drosophila Met and Tai genes. This reporter system gave highly reproducible results and showed nanomolar sensitivity to natural JHs. We then applied this reporter system to a structure-activity relationship (SAR) analysis of 14 natural and synthetic JHAs, leading to identification of the ligand structural factors important for the transcription-inducing activity.

CONCLUSION

Because this reporter system is not affected by the signaling cascade downstream of the JH receptors, it is suitable for evaluating the intrinsic activity of JHAs. The SAR results obtained in this study therefore provide invaluable information on the rational design of novel JHA insecticides.

Identification and in silico prediction of metabolites of tebufenozide derivatives by major human cytochrome P450 isoforms

Cytochrome P450 (CYP) enzymes constitute a superfamily of heme-containing monooxygenases. CYPs are involved in the metabolism of many chemicals such as drugs and agrochemicals. Therefore, examining the metabolic reactions by each CYP isoform is important to elucidate their substrate recognition mechanisms. The clarification of these mechanisms may be useful not only for the development of new drugs and agrochemicals, but also for risk assessment of chemicals. In our previous study, we identified the metabolites of tebufenozide, an insect growth regulator, formed by two human CYP isoforms: CYP3A4 and CYP2C19. The accessibility of each site of tebufenozide to the reaction center of CYP enzymes and the susceptibility of each hydrogen atom for metabolism by CYP enzymes were evaluated by a docking simulation and hydrogen atom abstraction energy estimation at the density functional theory level, respectively. In this study, the same in silico prediction method was applied to the metabolites of tebufenozide derivatives by major human CYPs (CYP1A2, 2C9, 2C19, 2D6, and 3A4). In addition, the production rate of the metabolites by CYP3A4 was quantitively analyzed by frequency based on docking simulation and hydrogen atom abstraction energy using the classical QSAR approach. Then, the obtained QSAR model was applied to predict the sites of metabolism and the metabolite production order by each CYP isoform.

Sequentially addressable dielectrophoretic array for high-throughput sorting of large-volume biological compartments

Droplet microfluidics has become a powerful tool in precision medicine, green biotechnology, and cell therapy for single-cell analysis and selection by virtue of its ability to effectively confine cells. However, there remains a fundamental trade-off between droplet volume and sorting throughput, limiting the advantages of droplet microfluidics to small droplets (<10 pl) that are incompatible with long-term maintenance and growth of most cells. We present a sequentially addressable dielectrophoretic array (SADA) sorter to overcome this problem. The SADA sorter uses an on-chip array of electrodes activated and deactivated in a sequence synchronized to the speed and position of a passing target droplet to deliver an accumulated dielectrophoretic force and gently pull it in the direction of sorting in a high-speed flow. We use it to demonstrate large-droplet sorting with ~20-fold higher throughputs than conventional techniques and apply it to long-term single-cell analysis of Saccharomyces cerevisiae based on their growth rate.

Direct measurement of 1-mN-class thrust and 100-s-class specific impulse for a CubeSat propulsion system

This paper presents the development of a thrust stand to enable direct measurement of thrust and specific impulse for a CubeSat propulsion system during firing. The thrust stand is an inverted pendulum and incorporates a mass balance for direct in situ mass measurement. The proposed calibration procedure allows precise performance characterization and achieves a resolution of 80 μN thrust and 0.01 g mass loss, by taking into account the drift of the thrust-stand zero caused by propellant consumption. The performance of a water micro-resistojet propulsion system for CubeSats was directly characterized as a proof of concept of the thrust stand. Continuous profiles of thrust, specific impulse, and mass consumption were acquired under various conditions in a single firing test. A thrust from 1 mN to 10 mN and a specific impulse from 45 s to 100 s with a maximum measurement uncertainty of ±15.3% were measured for the throat Reynolds number in the range 100-400.

A Fluorescent Compound from the Exuviae of the Scorpion, Liocheles australasiae

Most scorpions fluoresce under UV light. To date, two types of fluorescent compounds have been identified in scorpions, but it has been assumed that other unknown compounds may be responsible for the fluorescence. In this study, we isolated a fluorescent compound from the exuviae of the scorpion Liocheles australasiae identified as a macrocyclic diphthalate ester with a molecular mass of 496.2 Da. The same compound was also detected in extracts from four other scorpion species. This suggests that this compound is shared by multiple scorpion species, although its contribution to the cuticle fluorescence may be relatively small.

P832LDL-C levels on statins and cardiovascular event risk in stable coronary artery disease: An observation from the REAL-CAD study

Background

The relation between very low on-treatment low-density lipoprotein cholesterol (LDL-C) level and the cardiovascular event risk is still unclear in patients receiving the same doses of statins.

Methods

From the REAL-CAD study comparing high-dose with low-dose pitavastatin therapy in Japanese patients with stable coronary artery disease, 11105 patients without reported non-adherence for the study drug were divided into 3 groups according to the on-treatment LDL-C level at 6-month (<70 mg/dL, 70–100 mg/dL, and ≥100 mg/dL; N=1016, N=3078, and N=1665 in the pitavastatin 1 mg/day stratum; N=2431, N=2524, and N=391 in the pitavastatin 4 mg/day stratum). Primary outcome measure was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, or unstable angina requiring emergent admission.

Results

In the pitavastatin 1 mg/day stratum, cumulative 4-year incidence of the primary outcome measure was not significantly different across the 3 groups (5.0%, 5.7%, and 5.2%, P=0.51), while in the 4 mg/day stratum, it was significantly higher in the LDL-C ≥100 mg/dL group than in other groups (4.5%, 3.4%, and 9.1%, P<0.001). The adjusted risks of the LDL-C <70 mg/dL group relative to the LDL-C 70–100 mg/dL group (reference) remained insignificant for the primary outcome measure in both 1 mg/day and 4 mg/day strata (HR 0.84, 95% CI 0.58–1.18, P=0.32, and HR 1.25, 95% CI 0.88–1.79, P=0.22). The adjusted risk of LDL-C ≥100 mg/dL group relative to the reference group was not significant for the primary outcome measure in the 1 mg/day stratum (HR 0.82, 95% CI 0.60–1.11, P=0.21), while it was highly significant in the 4 mg/day stratum (HR 3.32, 95% CI 2.08–5.17, P<0.001). In the on-treatment LDL-C ≥100 mg/dL group in the 4 mg/day stratum, LDL-C increased by 6.3 mg/dL from baseline to 6-month despite dose escalation of pitavastatin from 1 mg/day to 4 mg/day, suggesting the presence of unreported poor adherence in this small subgroup.

Adjusted Effects of On-treatment LDL-C

Conclusions

Very low on-treatment LDL-C level (<70 mg/dL) was not associated with lower cardiovascular event risk compared with moderately low on-treatment LDL-C level (70–100 mg/dL) in patients receiving the same doses of statins. Too much emphasis on the target LDL-C strategy might mislead the clinical practice.

Acknowledgement/Funding

The Comprehensive Support Project for Clinical Research of Lifestyle-Related Disease of the Public Health Research Foundation.

P4544Impact of hyponatremia improvement on one-year outcomes in patients with acute decompensated heart failure

Background

Impact of hyponatremia improvement on prognosis in patients with acute decompensated heart failure (ADHF) remains unclear.

Methods

Patients hospitalized for ADHF at 19 hospitals in Japan were enrolled between October 2014 and March 2016. Hyponatremia was defined as serum sodium concentration less than 135 mmol/l. Primary endpoint was composite of all-cause death and heart failure rehospitalization one year after discharge.

Results

Among 3805 patients enrolled, 486 patients with hyponatremia at admission showed higher in-hospital mortality (13.3% vs. 5.4%, p<0.001). Of 486 hyponatremic patients, 396 patients were discharged alive. One hundred forty-three patients showed persistent hyponatremia at discharge (group P), whereas 253 patients showed improvement of hyponatremia (group I). Baseline characteristics are shown in the table. Patients in group I showed higher sodium concentration at admission (132±3 mmol/l vs. 130±4 mmol/l, p<0.001) and more increase in serum sodium concentration at discharge (7±4 mmol/l vs. 1±5 mmol/l, p<0.001). One-year survival rate free from primary endpoint was not different between the groups (56.4% in group P vs. 58.5% in group I, p=0.79). After adjusting for confounders, improvement of hyponatremia was not associated with better prognosis (hazard ratio 1.00; 95% confidence interval 0.70–1.45, p=0.99). Hyponatremia improvement showed significant interaction with left ventricular ejection fraction (LVEF) less than 40% (p=0.01). In patients with LVEF<40%, improvement of hyponatremia was associated with better prognosis (hazard ratio 0.48, 95% confidence interval 0.28–0.85, p=0.01) whereas not in patients LVEF≥40%.

Patient characteristics Group P (n=143) Group I (n=253) p value Age (years) 81 (72–86) 81 (72–87) 0.73 Female 71 (49.7) 110 (43.5) 0.24 Ischemic etiology 42 (29.4) 81 (32.0) 0.58 Prior hospitalization 62 (43.7) 98 (39.5) 0.42 SBP at admission (mmHg) 140±36 144±38 0.40 HR at admission (bpm) 92±23 95±29 0.27 Atrial Fibrillation 47 (32.9) 103 (40.7) 0.12 NYHA class IV 60 (42.2) 138 (54.8) 0.02 Intravenous inotropic use 35 (24.5) 59 (23.3) 0.80 LVEF <40% 54 (37.8) 95 (37.6) 0.97 Values are median (interquartile range), mean ± standard deviation or number (%).

Conclusion

Improvement of hyponatremia at discharge was not associated with better prognosis in patients hospitalized for ADHF.

P5320Reduction in high-sensitivity C-reactive protein by pitavastatin was associated with improved outcomes in Japanese patients with stable coronary artery disease: results from REAL-CAD study

Background

The effect of statins on lowering high sensitivity C-reactive protein (hs-CRP) as well as low density lipoprotein cholesterol (LDL-C) has been associated with reduced risk for cardiovascular events in patients with elevated hs-CRP. However, it remains unclear whether this statin effect applies to low-risk patients with stable coronary artery disease (CAD). In this pre-specified sub-study within the REAL-CAD trial, we explored the association between achieved LDL-C/hs-CRP levels and cardiovascular events in Japanese patients with stable CAD who were treated with pitavastatin 1 mg or 4 mg/day.

Methods

The REAL-CAD trial randomly allocated 13,054 patients with stable CAD to pitavastatin 1 mg or 4 mg/day. LDL-C and hs-CRP were measured at baseline and at 6 months after randomization. We excluded those patients without 6-month data and those with endpoint events before 6 months (N=1915). The primary endpoint of the study was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal ischemic stroke, or unstable angina requiring emergency hospitalization. Outcomes were assessed by landmark analysis beyond 6 months among 4 groups that were configured based on LDL-C (median) and hs-CRP (median) targets: achieving neither target, achieving LDL-C target only, achieving hs-CRP target only, and achieving both targets. Data were adjusted for baseline characteristics including age, gender, diabetes and baseline values of LDL-C and hs-CRP.

Results

Median LDL-C and hs-CRP levels were 88 mg/dL and 0.52 mg/L at baseline and 80 mg/dL and 0.48 mg/L after 6 months, respectively. There was no correlation between the change in LDL-C and hs-CRP levels from baseline to 6 months (correlation coefficient: 0.009, P=0.331). Of the 11,677 patients included in the study, 25.1% (N=2799) achieved both LDL-C and hs-CRP targets, 25.3% (N=2282) met neither target, 24.8% (N=2765) met only the hs-CRP target, and 24.7% (N=2753) met only the LDL-C target. Risk of primary endpoint occurrence was significantly lower in those achieving either or both targets than in those meeting neither target (Figure A). In the subgroup analysis stratified by the randomized dose of pitavastatin, the risk for the primary endpoint was significantly lower in patients achieving both targets in both the 1mg and 4 mg arms, and in patients achieving only hs-CRP target in the 1 mg arm (Figure B, C).

Figure 1

Conclusions

In this subanalysis of the REAL-CAD trial, the hs-CRP lowering effect of pitavastatin was independent from LDL-C lowering. Lower achieved hs-CRP was associated with lower risk for cardiovascular events in Japanese patients with stable CAD.

Acknowledgement/Funding

Public Health Research Foundation, The company manufacturing the study drug (Kowa Pharmaceutical Co Ltd) was one of the entities providing financial s

P6356Comparisons of clinical outcomes in patients with heart failure with preserved ejection fraction with and without atrial fibrillation: results from a multicenter PURSUIT-HFpEF registry

Background

The presence of atrial fibrillation (AF) has been demonstrated to be associated with poor clinical outcomes in heart failure patients with reduced ejection fraction.

Objective

This study aimed to elucidate the impact of the presence of atrial fibrillation (AF) on the clinical characteristics, therapeutics, and outcomes in patients with heart failure and preserved ejection fraction (HFpEF).

Methods

PURSUIT-HFpEF is a multicenter prospective observational study including patients hospitalized for acute heart failure with left ventricular ejection fraction of >50%. Patients with acute coronary syndrome or severe valvular disease were excluded.

Results

Of 486 HFpEF patients (age, 80.8±9.0 years old; male, 47%) from 24 cardiovascular centers, 199 (41%) had AF on admission. Patients with AF had lower systolic blood pressures (142±27 vs. 155±35mmHg, p<0.0001) and higher heart rates (91±29 vs. 82±26bpm, p<0.0001) than those without. There was no difference in the usage of inotropes or mechanical ventilation between the 2 groups. A higher quality of life score (EQ5D, 0.72±0.27 vs. 0.63±0.30, p=0.002) was observed at discharge in patients with than without AF. In addition, AF patients tended to demonstrate lower in-hospital mortality rates (0.5% vs. 2.4%, p=0.09) and shorter hospital stays (20.3±12.1 vs. 22.6±18.4 days, p=0.09) than those without. During a mean follow up of 360±111 days, mortality (14.1% vs. 15.3) and heart failure re-hospitalization rates (13.1% vs. 13.9%) were comparable between the 2 groups.

Conclusion

In contrast to heart failure patients with reduced ejection fraction, AF on admission was not associated with poor long-term clinical outcomes among HFpEF patients. Several in-hospital outcomes were better in patients with AF than in those without.

Acknowledgement/Funding

None

P4764Relationship of the duration of pulmonary vein isolation-refractory non-paroxysmal atrial fibrillation to the middle- to long-term outcome of the ExTRa Mapping-guided ablation

Introduction

It is reported that for patients with non-paroxysmal (persistent or long-standing persistent) atrial fibrillation (Non-PAF), extended ablation to atrial walls in addition to pulmonary vein isolation (PVI) did not improve the long-term outcome. On the other hand, modulation of Non-PAF drivers (or perpetuators) has been proposed as one of the alternative effective ablation strategies for Non-PAF.

Purpose

To clarify whether the rotor ablation under online real-time high-density phase mapping system is effective for PVI-refractory Non-PAF ablation.

Methods

Under such circumstances, our academic group had recently developed the online real-time high-density phase mapping system (ExTRa Mapping™) by industrial alliance. The phase map moving images were based on 41 intra-atrial bipolar signals recorded by a 20-pole spiral-shaped catheter (2.5 cm in diameter) and on in silicorapid prediction of spatio-temporal atrial excitations (artificial intelligence system). Then we applied the ExTRa Mapping to clinical practice in order to directly visualize rotors in patients with Non-PAF, and investigated the middle- to long-term outcome of the ExTRa Mapping-guided rotor ablation (ExTRa-ABL).

Results

Thirty-eight patients (63±8 y/o, 30 males) with Non-PAF demonstrating refractoriness to PVI were enrolled in this study. Ablation for cavo-tricuspid isthmus and/or superior vena cava isolation was additionally performed at physicians' discretion. After these procedures, the ExTRa-ABL was performed in order to modify Non-PAF substrates, causing rotor control. The modification of the rotors was evaluated by re-mapping with the use of the ExTRa Mapping at the end of each ablation session. Patients were followed at 1, 3, 6 months and every year after the procedure. All of them were followed for 21±8 months. During the follow-up period, Non-PAF was recurred in only 8 of 38 (21%). Furthermore, we found if PVI-refractory Non-PAF duration was shorter than 6 years, the non-recurrence rate remained ≥80% (see Figure), which was markedly better outcome comparing with previous reports with regard to Non-PAF ablation.

Figure 1

Conclusion

Comparing with conventional Non-PAF ablation strategies, our novel approach with the use of the online real-time high-density phase mapping system might improve medium- to long-term outcome of PVI-refractory Non-PAF treatment.